Location: Water Management and Systems Research
Title: Functional xylem characteristics associated with drought-induced embolism in angiospermsAuthor
LENS, FREDERIC - Naturalis Biodiversity Center | |
Gleason, Sean | |
BORTOLAMI, GIOVANNI - Naturalis Biodiversity Center | |
BRODERSEN, CRAIG - Yale University | |
DELZON, SYLVAIN - University Of Bordeaux | |
JANSEN, STEVEN - Ulm University |
Submitted to: New Phytologist
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 8/3/2022 Publication Date: 11/17/2022 Citation: Lens, F., Gleason, S.M., Bortolami, G., Brodersen, C., Delzon, S., Jansen, S. 2022. Functional xylem characteristics associated with drought-induced embolism in angiosperms. New Phytologist. 236(6):2019-2036. https://doi.org/10.1111/nph.18447. DOI: https://doi.org/10.1111/nph.18447 Interpretive Summary: Water must be transported from the soil to the leaves for gas exchange and growth to take place. This is accomplished through narrow conduits present in plant xylem tissue. The diameter of these conduits is one of the most frequently measured traits in drought tolerance studies. It is often assumed that wider and longer vessels are more susceptible to hydraulic failure, i.e., the loss of hydraulic conductance resulting from gas embolism in these conduits. We review here the possible linkages between embolism formation (and spread) and conduit diameter, including traits closely aligned with conduit diameter. We propose key knowledge gaps that need to be addressed to achieve a better understanding of acute drought stress in both crop and wild species, as well as the possible effects of climate change on vascular plant performance. Technical Abstract: Vessel diameter is the most frequently measured trait in structure-function studies of drought-induced embolism in angiosperm xylem. It is often assumed that wider and longer vessels are more susceptible to embolism formation than narrower and shorter vessels. However, a mechanistic explanation of the putative diameter-embolism resistance link is lacking, mainly because the drivers of drought-induced embolism remain puzzling. Here, we review data from comparative anatomy and xylem physiological studies, highlight potential anatomical (intervessel pit membrane thickness and other vessel traits) and physico-chemical (xylem sap and vessel wall composition) drivers of embolism formation, and put forward key knowledge gaps. A better understanding of the drivers behind drought-induced embolism is essential to develop accurate process-based models to predict how water transport in trees and crops is affected by drought, which is especially important due to ongoing shifts in temperature and precipitation at many places worldwide. |